[java] Add hooks around getScreenshotAs in WebDriverListener #16232

WebDriverListener has now default methods for both WebDriver and
WebElement for clients to be notified before and after a
screenshot is being taken.

Fixes #16232

Author: giulong

java/src/org/openqa/selenium/support/events/WebDriverListener.java

@@ -30,8 +30,10 @@
 import org.openqa.selenium.Cookie;
 import org.openqa.selenium.Dimension;
 import org.openqa.selenium.JavascriptExecutor;
+import org.openqa.selenium.OutputType;
 import org.openqa.selenium.Point;
 import org.openqa.selenium.ScriptKey;
+import org.openqa.selenium.TakesScreenshot;
 import org.openqa.selenium.WebDriver;
 import org.openqa.selenium.WebElement;
 import org.openqa.selenium.WindowType;
@@ -330,6 +332,26 @@ default void beforeResetInputState(WebDriver driver) {}
    */
   default void afterResetInputState(WebDriver driver) {}
 
+  /**
+   * This method will be called before {@link TakesScreenshot#getScreenshotAs(OutputType)} is
+   * called.
+   *
+   * @param driver - decorated WebDriver instance
+   * @param target - target type, @see OutputType
+   * @param <X> - return type for getScreenshotAs.
+   */
+  default <X> void beforeGetScreenshotAs(WebDriver driver, OutputType<X> target) {}
+
+  /**
+   * This method will be called after {@link TakesScreenshot#getScreenshotAs(OutputType)} is called.
+   *
+   * @param driver - decorated WebDriver instance
+   * @param target - target type, @see OutputType
+   * @param result - object in which is stored information about the screenshot.
+   * @param <X> - return type for getScreenshotAs.
+   */
+  default <X> void afterGetScreenshotAs(WebDriver driver, OutputType<X> target, X result) {}
+
   // WebElement
 
   /**
@@ -581,6 +603,24 @@ default void beforeGetCssValue(WebElement element, String propertyName) {}
    */
   default void afterGetCssValue(WebElement element, String propertyName, String result) {}
 
+  /**
+   * @param element - decorated WebElement instance
+   * @param target - target type, @see OutputType
+   * @param <X> - return type for getScreenshotAs.
+   */
+  default <X> void beforeGetScreenshotAs(WebElement element, OutputType<X> target) {}
+
+  /**
+   * This action will be performed each time after {@link WebDriver.TargetLocator#alert()} is
+   * called.
+   *
+   * @param element - decorated WebElement instance
+   * @param target - target type, @see OutputType
+   * @param result - object in which is stored information about the screenshot.
+   * @param <X> - return type for getScreenshotAs.
+   */
+  default <X> void afterGetScreenshotAs(WebElement element, OutputType<X> target, X result) {}
+
   // Navigation (WebDriver.Navigation)
 
   /**

java/test/org/openqa/selenium/support/events/EventFiringDecoratorTest.java

@@ -44,7 +44,9 @@
 import org.openqa.selenium.Dimension;
 import org.openqa.selenium.ImmutableCapabilities;
 import org.openqa.selenium.JavascriptExecutor;
+import org.openqa.selenium.OutputType;
 import org.openqa.selenium.Point;
+import org.openqa.selenium.TakesScreenshot;
 import org.openqa.selenium.WebDriver;
 import org.openqa.selenium.WebDriverException;
 import org.openqa.selenium.WebElement;
@@ -285,9 +287,11 @@ public void afterPerform(WebDriver driver, Collection<Sequence> actions) {
 
   @Test
   void shouldFireWebElementEvents() {
+    String result = "result";
     WebDriver driver = mock(WebDriver.class);
     WebElement element = mock(WebElement.class);
     when(driver.findElement(any())).thenReturn(element);
+    when(element.getScreenshotAs(OutputType.BASE64)).thenReturn(result);
 
     CollectorListener listener =
         new CollectorListener() {
@@ -467,6 +471,16 @@ public void beforeGetCssValue(WebElement element, String propertyName) {
           public void afterGetCssValue(WebElement element, String propertyName, String result) {
             acc.append("afterGetCssValue").append("\n");
           }
+
+          @Override
+          public <X> void beforeGetScreenshotAs(WebElement driver, OutputType<X> target) {
+            acc.append("beforeGetScreenshotAs ").append(target).append("\n");
+          }
+
+          @Override
+          public <X> void afterGetScreenshotAs(WebElement driver, OutputType<X> target, X result) {
+            acc.append("afterGetScreenshotAs ").append(target).append(" ").append(result).append("\n");
+          }
         };
 
     WebDriver decorated = new EventFiringDecorator<>(listener).decorate(driver);
@@ -485,6 +499,7 @@ public void afterGetCssValue(WebElement element, String propertyName, String res
     element1.getSize();
     element1.getCssValue("test");
     element1.clear();
+    element1.getScreenshotAs(OutputType.BASE64);
 
     assertThat(listener.acc.toString().trim())
         .isEqualTo(
@@ -545,7 +560,11 @@ public void afterGetCssValue(WebElement element, String propertyName, String res
                 "beforeAnyWebElementCall clear",
                 "beforeClear",
                 "afterClear",
-                "afterAnyWebElementCall clear"));
+                "afterAnyWebElementCall clear",
+                "beforeAnyWebElementCall getScreenshotAs",
+                "beforeGetScreenshotAs OutputType.BASE64",
+                "afterGetScreenshotAs OutputType.BASE64 " + result,
+                "afterAnyWebElementCall getScreenshotAs"));
   }
 
   @Test
@@ -973,6 +992,40 @@ public void afterAlert(WebDriver.TargetLocator targetLocator, Alert alert) {
                 "afterAnyCall alert"));
   }
 
+  @Test
+  void shouldFireWebDriverTakesScreenshotEvents() {
+    String result = "result";
+    WebDriver driver = mock(WebDriver.class, withSettings().extraInterfaces(TakesScreenshot.class));
+    when(((TakesScreenshot) driver).getScreenshotAs(OutputType.BASE64)).thenReturn(result);
+
+    CollectorListener listener =
+      new CollectorListener() {
+        @Override
+        public <X> void beforeGetScreenshotAs(WebDriver driver, OutputType<X> target) {
+          acc.append("beforeGetScreenshotAs ").append(target).append("\n");
+        }
+
+        @Override
+        public <X> void afterGetScreenshotAs(WebDriver driver, OutputType<X> target, X result) {
+          acc.append("afterGetScreenshotAs ").append(target).append(" ").append(result).append("\n");
+        }
+      };
+    WebDriver decorated = new EventFiringDecorator<>(listener).decorate(driver);
+
+    ((TakesScreenshot) decorated).getScreenshotAs(OutputType.BASE64);
+
+    assertThat(listener.acc.toString().trim())
+      .isEqualTo(
+        String.join(
+          "\n",
+          "beforeAnyCall getScreenshotAs",
+          "beforeAnyWebDriverCall getScreenshotAs",
+          "beforeGetScreenshotAs OutputType.BASE64",
+          "afterGetScreenshotAs OutputType.BASE64 " + result,
+          "afterAnyWebDriverCall getScreenshotAs",
+          "afterAnyCall getScreenshotAs"));
+  }
+
   @Test
   void shouldSuppressExceptionInBeforeAnyCall() {
     WebDriver driver = mock(WebDriver.class);